Fluid pump



2 Sheets-Sheet l INVENTOR. HHRTLINE FLUID PUMP Filed April 22,v 1942 July 4, 1944. Y

July 4; 1944 R. E. HARTLINE 2,353,031

FLU'ID PUMP Filed April 22, 1942 2 Sheets-Sheet 2 E N 1 3 mu m TT NR W En n .6.. 6 a# W0/ ,d J E@ M T fw. m/# m ,f Y, -3 l/\\ Z my Y. a. w// Im .J B J w w w -21. -VMH k HW l 9; Y ,ivf 6 f J w.

Patented July 4, 1944 FLUID PUMP Ralph E. Hartline, Swissvale, Pa., assigner to Mine :Safety Appliances Company,

Pittsburgh,

Application April'22, 1942, Serial No. 439,959 (o1. 23o-117) 3 Claims.

A'Ihis linvention relates 'to a fluid pump and,

.moreparticularlnto the type of pumpadaptable sive and elaborateseals were used, considerable maintenance' was involved, `maliing continuous operation difficult.

It vis ,amongY the objects oi .this invention .to provide Ya pump of simple construction which overcomes theioregoing objections, which can be readily attached to a ,drivingine'ana which is of Asuchconstruction that no enclosure is required for sealing oithe pumping unit toaproducea difference in pressure andlflow of fluid, which is inexpensive in construction and which requires a small amount of .power in its operation.

It is a more speciiic .object of this invention to provide a pump having arotatable impeller which operates as a pump meansrand which is so constructed thai-,it initself forms a complete pumping unit for producing the difference in .pressure/.desired-and requires 'merely its connection to a driving means and toa fluid-duct to'prokduce a continuous ow such `as is adequate for moving a gasv sample through `a A.detectingr ap- .paratus.- Y Y 'fr Other objects yof :this invention will become Yap parent from a description.ofapreferred-embodiment of my invention. l

:In Vthe drawingszy g Fig. 1v isa l.plan View partly in section `of a `preferred emloodiment .oim-y-invention andillustrates .one arrangement otits .connection to a motor actingas a driving means Vvfor the pump and as a lmeans ,ofuconnection to agas sampling line; I l

'2 is an end elevational View of the embodiment illustrating inaddition the vvmounting of the driving means to a bracket; v

Fig; B isanother end elevational vview partly in section and enlarged to illustrate more clearly the passages formed for connecting the impeller inrit to a duct formed in passages or pumping a'driving shaft;

i 4 is a sectional 'View 'li- -ofFiggB; g

F-igg is -a sectional YView taken along the-line taken along the line rtains an explosive mixture.

Fig. 6 is a detailed view of the individual parts making up the shaft attaching member for the impeller in connecting itito a driving'shaft; and

Fig. 7' is an end elevational view of the shaft attaching member. y

In describing my invention, reference ris continually made to its application for moving continuouslysmall samples through a gas detecting apparatus,v and Ait is intended that this operation include moving suchvolumes 'as'l o'f Va cubic foot per minute at a difference in pressure of about 2,4 inches'v of Water. One such application isl an alarm apparatus for mine use where the apparatus operates in drawing a sample continuou'sly from a certain atmosphere and is operative to give warningzin thefevent the atmosphere con- It is to vbe understood, however, that applications other than for gas sampling can be made of this invention where these iiow and pressure conditionsare of advantage and useful, f

Invention ispredicated on the principle of rotating an impeller containing small radialpassages -each connected'to'a centralhub chamber which in turn is connected to a'fluid duct through which fluid is to be moved. It has been found that rotation of thesesmall radial passages in the *atmosphere formed 'about the body of the impeller produces a suctionn the central hub chamber to such an extent that the diierential `pressure produced is adequate for accomplishing movement of small volumesr of gas. In thepreferred arrangement, the central hub chamber .is attached `to a hollow4 driving shaft 4which acts as a connecting means 'to aduct vconnected in turn to a gas detecting apparatus.Y

:In .the embodiment, the impelleri is made ,preferably of some suitableV plastic material 4such as any of the phenolic resins orl cellulose derivative materials.V The impeller is about 1A 'thick and, because of the nature of the materialof which it is constructed, is relatively light in weight. It is recognized that' the impeller may be made of `any other .material that is practical for this purpose such,for. example, as metal.

Formed inthe body `of theimpeller l and extending radially 'from the periphery to itsr center are smallpassages 3 about sae indiameter and about 1%k' long. The impeller l is mounted on to a hollow driving shaft. 5 by using a .hub or shaft mounting means 6. This mounting means is made upY of two parts ,ta'andl' 6d (seeligs. 6 and '7) and contains extending passagessa which A'connect the radial passages 3 to ay chamber or shaft 5. These passages 3a are formed in the end surface of one part 6a of the shaft mounting means 6 and can be readily formed by merely cutting into the surface. The portion 6a has a hub surface 6b for receiving the impeller body and engaging its inner surface 3b. In addition, a flange 6c extends up on to the side of the impeller and back of the hub and cooperates with the other portion Scl of the shaft mounting means 6. This portion 6d ts onto the opposite surface of the impeller body and is fastened to the first portion 6a. by means of screws 6e that pass through the flange or plate portion Iid into threaded openings of the impeller carrying portion 6a. With this arrangement, the assembly of the shaft mounting means 6 is made by inserting portion 6a through the central opening in the impeller body defined by the surface 3b' so that the flange Sc abuts the surface of the body and placing the other portion Bd on the opposite side of the body and holding it in place and drawing it tightly against the end surface of the impeller means of the screws 6e. With this assembly, the radial passages 3 are sealed from the atmosphere except through the passage I formed in the 'portion 6a and a continuing passage 'Ib provided in the hollow drive shaft 5.

In the embodiment of the invention illustrated, the driving means represented is an electric motor IIJ to which the hollow driving shaft is attached. The shaft 5 extends outwardly sufliciently on the driving end to accommodate the fluid pump. On the opposite end of the shaft is a setling chamber supplied for sealing olf the bearing I2 for the motor. Ordinarily, a dust plate is placed to enclose the lubricating chamber II for the bearing and in the modification made for my application, a plate I3 is fastened to the housing of the motor, which, by means of a washer I 4, seals off the chamber II. Within the chamber a felt 'washer I5 encircles the bearing and supplies the lubrication for the bearing. When used in connection with my application, this felt washer does not interfere with the small fiuid chamber formed at the end of the shaft. A threaded opening in the end sealing plate I3 receives a duct I8 through which fluid is to be moved. If my invention is used with an apparatus for gas detection, this duct is connected to the gas detecting apparatus, not shown, and the invention is operated to move a gas sample -continuously through the apparatus.

One suitable means for connecting the duct I8 to the chamber II is by a coupling I6 which is threaded directly to theend plate and which has a threaded end for receiving a connection I1. This connection I1 holds and seals off a sleeve I9 which has a flared end that seats against a surface of the connection I1 and the coup-ling I6. This 4sleeve extends into the duct I8 a sufcient `distance to be held tightly thereto. With this arrangement, no diiiiculty is encountered in sealing oif the moving parts, and in this instance the only moving part is the motor shaft which is ordinarily sealed for lubricating purposes. The important advantage is that no seal is necessary for the pump because it is operative merely by its rotation in the atmosphere, unlike an ordinary centrifugal pump which has a rotating body cooperating with an enclosure to produce a pressure or ow.

In the operation of the pump, the motor supplied should be adequate for rotating the impeller at reasonably high speeds and in the embodiment, it has been found that a rotation of giving the flow conditions specied above. It is to be pointed out that with this improved pump, the pump or whole impeller is readily attached to some form of a driving shaft which need only be bored in some manner so that it can be conveniently connected to a duct supplying a source of iiuid. This feature of adaptability along with the advantage of low cost of construction and operation makes the development of importance.

The pump is supplied complete and can be mounted directly on to some form of hollow shaft by means of a key 20 that passes through the shaft about 5,000 revolutions perminute is adequate for V mounting means and engages the driving shaft. In the assembly shown, a -motor mounting bracket `25 and shock absorber assembly 25a are illustrated diagramm'atically for the purpose of completeness and to show how the motor can be attached to a support 26. The support illustrated is an enclosure for the whole apparatus and if tightly sealed about and at its engagement with the plate I3 at I3a and at the absorber connection to the enclosure must be provided with a suitable outlet, indicated at 30, to discharge the fluid moved. If this arrangement is used, a duct ris attached to the enclosure for receiving the fluid discharged through the opening and to transport it to some remote location. In this way, the pump can be used for discharging iiuid into a duct as Well as drawing fluid from a duct.

It is recognized that certain deviations can be made from this specific embodiment of this invention herein described and that other embodiments can be made, and it is intended that the invention include all such modifications and embodiments, although it is to be recognized that the specific embodiment represents a desirable and successful application of the principle involved in my invention and is actually a pump now being used successfully in connection with gas sampling apparatus where a continuous flow of small volume is desired. Variation in size of the structure varies the capacity of the pump. Although emphasis has been placed on an application of my invention to gas sampling apparatus, and other and equally important applications can be made as are obvious to those requiring such apparatus.

While I have described my inventien in accordance with the provisions of the patent statutes and have explained the principle and mode of operation of my invention, and have illustrated and described what I now consider to represent its best embodiment, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as sperifically illustrated and described.

I claim:

1. A centrifugal fluid suction pump comprising a driving means having a drive shaft with a longitudinal passageway, one end of the shaft being connectable to a source of fluid, the other end of the shaft providing a driving means, a plastic impeller member with a hollow central portion and having radial passages extending inwardly from its periphery to the hollow portion, a shaft mounting means attached to the surface defining the hollow central portion of the impeller and having an inner surface for receiving the driving shaft, the shaft mounting means being attached to the end portion of the shaft and extending beyond the shaft to define a connecting chamber for the radial passages and thepassageway of the shaft and having a flange extending onto one surface of the impeller body, means formed in the end 0f the shaft mounting means for fluidly connecting the radial passages of the impeller merinber to the connecting chamber, and an outer sealing plate attached to the opposite surface of the impeller body and attached to the outer surface `of the shaft mounting means for sealing off the ,passage means connecting the radial passages to the passage of the shaft.

2. A centrifugal suction pump comprising a motor having. a hollow driving shaft, one end of the shaft being fluidly connected to a source of fluid, the other end of the shaftI being connectable to a driven means, a thin plastic impeller body mounted to the end portion of the shaft, radial passages formed in the body and extending from the periphery to an inner surface defining a central hollow section, a shaft mounting means attached to the end portion of the shaft and to the surface of .the impeller body defining the central hollow section and op erative to drivingly support the impeller body on to the shaft, the shaft mounting means extending beyond the shaft and having, passages formed in its outer end fluidly connecting the radial passages of the impeller body to the hollow shaft, the shaft mounting means having a flange extending onto a side surface of the impeller body, a flat plate positioned on to the opposite side of the' impeller body and fastened to the end of the shaft mounting means for sealing in cooperation with the flange of the shaft mounting means the impeller body to the shaft and closing to the atmosphere the passage means connecting the radial passages of the impel-ler body to the hollow shaft.

3. A centrifugal suction pump for gas sampling comprising a circular disc provided with a plurality of radial passages extending from its periphery to its central portion, an electric motor provided with a hollow drive shaft extending therethrough and projecting from an end of the motor, said disc being rigidly mounted on said projecting end of the shaft with the inner ends of said passages in communication with the interior of the shaft, a stationary conduit in cornmunication with the opposite end of the shaft and adapted to be connected to a source of gas, and means sealing the connection between the adjacent ends of the drive shaft and stationary conduit.

RALPH E. HARTLINE. 

